Curing soap in glassine bag?

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dixiedragon

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I got a box of glassine bags from my local restaurant supply store. I'm wondering if I can put my fresh-cut soap directly in these bags to let them cure? I have pets and keeping pet hair off the soap is a challenge!
 
Edited in light of other responses:
Lack of air circulation may cause rancidity, particularly for the fresh soap which is still chock full of water.
I would not use the air-tight bags as a solution to pet fur, as I feel it may cause more problems than it solves.
 
Last edited:
...If you seal the bars in bags, you absolutely will have rancid soap, probably within a few weeks. Sealed fresh bar soap is also one of the few ways to get moldy soap.

Are you speaking in such absolutes based on what "everybody assumes to be true"? Or have you actually tried this to learn for yourself whether the soap goes rancid or gets moldy?

Honestly, I've done this. No, the soap doesn't go rancid. And, no, it doesn't get moldy either -- as long as the soap maker is smart about not putting large pieces of food (oatmeal, coarse coffee, flower petals, etc.) on or in the soap. But if that's the case, the soap might get moldy even if stored in the open air.

***

@dixiedragon -- What I have found to work better than putting bars into individual plastic bags is to put the bars into an open tray or box and cover the top with clean cotton toweling or light plastic sheeting. An alternative is to enclose the entire tray or box with something like a cloth pillowcase or (shock! horror! sacrilege!) a plastic bag.

Use any kind of suitable lightweight material that will protect the soap from dust and other contaminants. For the past couple of years, I have been putting each box of soap into a very thin plastic bag right after I get the bars cut and detailed. I tuck the open end of the bag under the box to close it and "tent" the plastic above the top of the box so the plastic doesn't touch the soap.

The water evaporating from the soap must be allowed to dissipate. If this doesn't happen, a slick layer of glycerin and water will collect on the soap bars, which is a sign there isn't enough airflow. The wet surface of the soap can get marred with fingerprints, etc., simply because the soap is softer and easier to damage. This wetness is not rancidity nor mold, just to be clear, and it clears up nicely when the soap is able to dry off.

With a cloth cover, the airing-out and dissipation of moisture happens naturally without the soap maker's help.

If a plastic bag or plastic sheeting is used, you must air out the inside of the bag at least once a day for about two weeks to help the moisture dissipate. If you put each bar into individual plastic bags, it will take a lot of time to air out every one of those bags daily. Also the soap is at more risk of being damaged by all the handling and by the fact that you can't keep a small bag from touching the soap.

Just my two cents. I hope it gives you some useful ideas, Dixie.
 
If pet hair is a challenge, go to the fabric store and buy some cheesecloth or lightweight muslin to lay across your curing soaps. Both are thin enough to allow for air circulation.
 
Are you speaking in such absolutes based on what "everybody assumes to be true"? Or have you actually tried this to learn for yourself whether the soap goes rancid or gets moldy?

Honestly, I've done this. No, the soap doesn't go rancid. And, no, it doesn't get moldy either -- as long as the soap maker is smart about not putting large pieces of food (oatmeal, coarse coffee, flower petals, etc.) on or in the soap. But if that's the case, the soap might get moldy even if stored in the open air.

***

@dixiedragon -- What I have found to work better than putting bars into individual plastic bags is to put the bars into an open tray or box and cover the top with clean cotton toweling or light plastic sheeting. An alternative is to enclose the entire tray or box with something like a cloth pillowcase or (shock! horror! sacrilege!) a plastic bag.

Use any kind of suitable lightweight material that will protect the soap from dust and other contaminants. For the past couple of years, I have been putting each box of soap into a very thin plastic bag right after I get the bars cut and detailed. I tuck the open end of the bag under the box to close it and "tent" the plastic above the top of the box so the plastic doesn't touch the soap.

The water evaporating from the soap must be allowed to dissipate. If this doesn't happen, a slick layer of glycerin and water will collect on the soap bars, which is a sign there isn't enough airflow. The wet surface of the soap can get marred with fingerprints, etc., simply because the soap is softer and easier to damage. This wetness is not rancidity nor mold, just to be clear, and it clears up nicely when the soap is able to dry off.

With a cloth cover, the airing-out and dissipation of moisture happens naturally without the soap maker's help.

If a plastic bag or plastic sheeting is used, you must air out the inside of the bag at least once a day for about two weeks to help the moisture dissipate. If you put each bar into individual plastic bags, it will take a lot of time to air out every one of those bags daily. Also the soap is at more risk of being damaged by all the handling and by the fact that you can't keep a small bag from touching the soap.

Just my two cents. I hope it gives you some useful ideas, Dixie.
For a while, I was sticking a bar from every batch in a medium sized cardboard box for long-term storage, spaced out within the box. I realized they each got DOS in around 3 weeks, compared to their open-air batch-mates which have none. All was kept in air-conditioned comfort. 3 different recipes, no food, back when I was using citric acid as the chelator with appropriate lye- I ceased the experiment before the 4th soap showed any signs. The box now holds my growing FO collection. I briefly experimented with putting a bar per soap box, for a few older bars, and also saw DOS, their open-air batch-mates still showing none. My interest in testing the experiment with Sodium Gluconate as the chelator is low.
I thought my sample size was sufficient for my confidence, but as your experience contradicts it, I'll amend my post.
Edited for clarity.
 
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It's good to know you have put a fair bit of effort into testing this matter. Thank you for being willing to share your insights and experiences because that information gives authority to your opinions and advice.

I think it's also good when a person can research what other people have learned from their experiences and experiments.

So many soap makers unfortunately do neither -- they rely on gut-level "common sense;" or they blindly accept "it's always been done that way, so that's the way it must be done;" or they assume something to be true based on just one limited experience. That's why I question a person's point of view when I hear "always" and "never" being used.

It's good we are able to pool our respective insights and results.
 
It's good to know you have put a fair bit of effort into testing this matter. Thank you for being willing to share your insights and experiences because that information gives authority to your opinions and advice.

I think it's also good when a person can research what other people have learned from their experiences and experiments.

So many soap makers unfortunately do neither -- they rely on gut-level "common sense;" or they blindly accept "it's always been done that way, so that's the way it must be done;" or they assume something to be true based on just one limited experience. That's why I question a person's point of view when I hear "always" and "never" being used.

It's good we are able to pool our respective insights and results.
Thank you, and in editing my post I was surprised by how definite I was. I must have been typing hangry, because I usually try to leave room for discussion. 😞 And over lunch it occurred to me that I probably haven't shared my compact soap storage DOS woes, because it seemed like such a clear pattern that I was never really scratching my head about what I was seeing, so your consternation about my viewpoint and my tone were more than justified.
 
I got started with my "cure soap in a plastic bag" project because I wanted to learn what happens if I slowed the rate of evaporation during the first few days after CP soap is cut and put away to cure.

One thing I wondered -- If I slowed the initial rate of evaporation, would the soap get less ash -- either soda ash or soap crystal ash?

This ash seems to form during saponification or in the first few days after the bars are cut. My soap tends to form a haze of soap crystal ash on the bar tops -- I don't normally see soda ash. I don't want to steam or wash or spritz the soap -- too much fiddling for me. But what if there's a lazy woman's way to deal with ash?

Another thing I was wondering about was if I slow the rate of evaporation, would that also preserve a higher amount of scent in the soap?

I use fragrances that stick and are strong, but if it's possible to minimize the loss of scent during cure, then my customers and friends will get a "stinkier" soap, and that will make them happy. And perhaps I can get by with using a little less fragrance, reduce my costs a bit, and that will make me happy.

I don't have good ways to objectively measure these properties, especially the amount of scent retention. As far as scent goes, this curing in a bag method definitely hasn't hurt scent retention, but I don't have a way to know if it's improved retention. What is true is the scents from the soap in the room air is much lower, and that's a good thing for a soap maker's health.

I do think there's a little less soap crystal ash on my soap, and I'm content with that. It hasn't entirely gone away, however, so if a person is looking for a sure fire cure, this isn't it.

I guess the unexpected thing I learned from these tests is soap can cure just fine in a plastic bag if the soap is aired-out regularly. It only takes a few seconds once a day to air-out each box of soap, so it's not a big hardship.
 
Only to address the sealing of fresh soap in an fairly airtight plastic container: Soap dough is made this way and it does not mold in my experience. Also I have sealed entire loaves of newly made soap in plastic wrap to keep them from hardenting up too fast before I could use them for an intaglia design at a later date, and the loaves did not mold or go rancid either. The soap dough stays pliable. The loaves of soap remained soft enough to cut into bars with my multiple-bar wire cutter. And they don't get ash, which is a nice perk. At least that is my experience with the loaves I have wrapped thus. I think it was 5 loaves.
 
For a while, I was sticking a bar from every batch in a medium sized cardboard box for long-term storage, spaced out within the box. I realized they each got DOS in around 3 weeks, compared to their open-air batch-mates which have none. All was kept in air-conditioned comfort. 3 different recipes, no food, back when I was using citric acid as the chelator with appropriate lye- I ceased the experiment before the 4th soap showed any signs. The box now holds my growing FO collection. I briefly experimented with putting a bar per soap box, for a few older bars, and also saw DOS, their open-air batch-mates still showing none. My interest in testing the experiment with Sodium Gluconate as the chelator is low.
I thought my sample size was sufficient for my confidence, but as your experience contradicts it, I'll amend my post.
Edited for clarity.


Another factor could be the box itself. A few years ago when I mentioned that I use the cut-down cardboard boxes from grocery stores (free & abundantly available) to cure my soap, someone mentioned that the produce boxes could very well introduce contaminants to the soap and to watch for that. I always line the cardboard with paper towels or newsprint, then place meshed plastic so the soap does not sit directly on top of cardboard or paper. But with that warning I became more conscious of making sure the soap doesn't touch even the sides of the cardboard, especially as I re-use the cardboard as long as it is in good shape & don't want to introduce contaminants.
 
Another factor could be the box itself. A few years ago when I mentioned that I use the cut-down cardboard boxes from grocery stores (free & abundantly available) to cure my soap, someone mentioned that the produce boxes could very well introduce contaminants to the soap and to watch for that. I always line the cardboard with paper towels or newsprint, then place meshed plastic so the soap does not sit directly on top of cardboard or paper. But with that warning I became more conscious of making sure the soap doesn't touch even the sides of the cardboard, especially as I re-use the cardboard as long as it is in good shape & don't want to introduce contaminants.
It was lined on all sides with the same brand-new plastic mesh I use to line all my curing trays, and the box was also brand-new. But it was a decorative, hard cardboard box, so maybe there was a chemical component that somehow contributed to rancidity? I know soap dough is frequently kept for a while, but I thought it kept best with a vacuum seal or similar air-tight packaging. Sort of like an all-or-nothing, open-air or vacuum-seal situation where middling it gets bad results? But the more I'm hearing from this thread, the more I'm wondering if my results were the exception, not the rule.
 
@DeeAnna - I really think using a dehumidifier significant decreases soda ash. I have a fellow soaping friend and we do most everything pretty similar - we both used a lard-based recipe, we both use tap water from the same system, we order FOs from the same suppliers. And yet I have no ash and she has ash. The only difference I can see - dehumidifier.
 
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